Plain bearing materials made up of a system of layers comprising a metallic substrate material and a sliding layer, usually in the form of a plastic, are used for a wide variety of applications in which parts that are movable in relation to one another are to be connected to one another in a pivotably or translatorily sliding manner. They are suitable for the production of plain bearing bushes. These in turn are used variously in hinges and bearings of extremely different types, in particular in the automobile sector. Door hinges, seat adjusting systems, pedals, luggage compartment hinges, steering column adjustment mechanisms or shock absorbers may be mentioned here purely by way of example.
The plain bearing material that is used in these cases, which, depending on the application, is in the form of a plain bearing surface or a plain bearing bush, is maintenance-free, i.e. lubrication of the bearings is not required.
A self-lubricating plain bearing material is known from EP 0 998 637 B1. This plain bearing material comprises a metallic substrate material and a sliding layer arranged over the latter. The plain bearing material is designed for high compressive loads in the range of 200 MPa. The surface of the substrate material is highly structured to prevent such compressive loads from causing creep of the sliding layer. The sliding layer, preferably comprising a fluoropolymer, such as polytetrafluoroethylene (PTFE), is laminated onto the substrate material and firmly anchored in structure.
Generally, this plain bearing material has a bronze plating as an intermediate layer, in which the structuring is engraved. The substrate material itself may consist of various metallic materials, in particular steel or aluminum.
As discussed above, this sliding material known from the prior art is distinguished by a very high compressive load-bearing capacity, the tendency of the sliding material to creep during operation being counteracted by a very pronounced structuring of the substrate surface or by the strength of the substrate. These properties make it suitable for use for example in vehicle door hinges or the especially loaded front shock absorbers of a motor vehicle.
The disadvantage of this plain bearing material is that it requires very high production accuracy for the bearing housings to be lined with the plain bearing material, in order to ensure an exact fit of the plain bearing material in the bearing housing.